Sip

Experimenting with SIP and call timing on a gateway

One of the fundamental functions of many home and business gateways is to act as a SIP ALG (Application Layer Gateway) for setting up, routing, and terminating VoIP telephone calls. This presents some difficulty with Network Address Translation (NAT) functionality that we’ve covered before. However, there’s other functional behavior when it comes to SIP call setup and the resulting RTP streams that can be missed without some rigorous experimentation. Read more...

Testing SIP Aware Routers

Testing SIP aware CPE routers is a critical part of an over-all Voice over IP test strategy. CDRouter is perfect for testing SIP aware routers using a real world test setup. Using the CDRouter SIP test module, network and QA engineers can quickly verify the behavior of a SIP aware device and avoid costly interoperability problems. SIP and NAT SIP has become the leading signaling protocol for establishing Voice over IP calls between soft-phones and other VoIP applications. Read more...

What NAT ALGs does CDRouter test?

CDRouter includes test cases for the following NAT ALGs: FTP DNS ICMP H.323 (outbound and inbound) MSN Messenger RTSP SIP IPSEC (IKE and IPSEC ESP) PPTP CDRouter also runs several applications through the device under test that do not require a full NAT ALG. These include: HTTP HTTPS SMTP POP3 TFTP